Magnetic driving tool



Sept. 27, 1955 CLARK 2,718,806

MAGNETIC DRIVING TOOL Filed June 23, 1949 IN VEN TOR.

B WJ

United States Patent MAGNETIC DRIVING TOOL Frederick G. Clark, Buffalo,N. Y., assignor of one-half to Wade Stevenson, Buffalo, N. Y.

Application June 23, 1949, Serial No. 100,911

2 Claims. (Cl. 81125) This invention relates to improvements in magnetictools of the type in which the workpiece, such for example as a screw,bolt, nut, or the like to be driven is held on the tool by magneticforce to facilitate placing the workpiece into position to be driven.

One of the objects of this invention is to provide a magnetic tool whichincludes a magnet permanently mounted on the tool, and a tubular socketmember which is readily removable from the tool, so that it can easilybe replaced by another socket member, when worn, or by socket membersformed to operate on workpieces or parts of other sizes. It is also anobject of this invention to provide a tool of this type in which themagnet is permanently mounted on a portion of the tool in such manner asto be protected against strains or impacts, and in which the drivingforce is applied to the removable socket member independently of themagnet. A further object of this invention is to provide a magnetic toolof this type with a socket removably mounted on the tool and reversibleso that either end of the socket may be used to apply rotary motion ortorque to a workpiece.

Other objects and advantages will be apparent from the followingdescription of one embodiment of the invention and the novel featureswill be particularly pointed out hereinafter in connection with theappended claims.

In the accompanying drawings:

Fig. 1 is a longitudinal view, partly in section, of a magnetic toolembodying this invention.

Fig. 2 is an end view thereof.

Fig. 3 is a longitudinal view of the tool with the socket removedtherefrom.

Fig. 4 is an end view thereof.

Fig. 5 is a longitudinal view, partly in section, of the magnetic toolhaving a reversible socket mounted thereon.

Fig. 6 is an end view thereof.

Fig. 7 is a fragmentary longitudinal view of the magnetic tool shown inFigs. 5 and 6 with the socket removed therefrom.

Magnetic tools, such, for example, as socket wrenches, have heretoforebeen provided with a magnet permanently secured within the socketportion of the wrench, which magnet holds a nut or other workpiece inthe socket while the same is being applied to a structure. When socketwrenches of this type are continuously and severely used, the sockets ofthe wrenches rapidly become worn so that the entire wrench including themagnet must be discarded. Since the sockets of wrenches of this type aremuch less expensive than the magnets, I have provided a tool in whichthe sockets are removable when worn and replaceable by other sockets,without requiring the replacing of the magnet.

In the particular embodiment of the invention illustrated by way ofexample in Figs. 1 to 6, 10 represents a shank of a magnetic tool andwhich may be rotated, either manually by means of a handle (not shown)applied to one end thereof, or which may be driven by Patented Sept. 27,1955 means of a power operated device. This shank may be of any suitableor desired form and material and may be either of a magnetic ornon-magnetic material, the outer end of the shank being provided with anextension 11 on which a magnet may be suitably supported. For example,the end of the extension 11 may be provided with an aperture or recessat the outer end thereof within which a magnet 12 is suitably secured.The extension 11 of the shank is made of a non-magnetic material, andconsequently, if the shank 10 is also of nonmagnetic material, theextension 11 thereof may be formed integral with the shank. If, on theother hand, the shank is made of magnetic material, then the extension11 thereof is made of non-magnetic material and is rigidly secured tothe shank. For example, the shank may be provided with an enlargedportion 14 which may be recessed to receive the inner end of theextension 11 as shown in Fig. 5. The extension consequently forms anon-magnetic sheath about the sides and inner end of the magnet.

The extension 11 is formed to enter into a tubular socket 15 andsuitable means are also provided to impart rotation to the socket whenthe same is in operative relation to the extension 11. For this purpose,in the construction shown by way of example, the extension 11 isprovided at the portion thereof adjacent to the enlargement 14 of theshank with a portion 17 which is non-circular in cross section, forexample, square is shown in Figs. 3 and 4. The outer portion 18 of theextension may be of circular cross section. The socket member 15 is,consequently, also provided at least at the inner end thereof with alongitudinally extending bore or passage which is square in crosssection or of other form so that torque applied to the shank 10 may betransmitted to the socket 15. Preferably the portion of the bore of thesocket which extends about the extension 11 is of uniform cross sectionthroughout its length, and the part 18 of circular cross section is ofsuch diameter that the extension 11 may readily be inserted into thesocket. The enlargement 14 of the shank acts as a stop to limit themovement of the shank about the extension 11.

The outer end of the socket which extends beyond the outer end of themagnet 12 may be provided with a recess 19 of any suitable or desiredcross sectional form for engagement with a workpiece or part, such forexample, as a nut or head of a bolt or screw.

The sockets may be removably held on the extensions 11 of the magnetictool in any suitable or usual manner. In the construction shown by wayof example in Figs. 1 to 4, the extension 11 is provided with atransversely extending recess 20 in which a spring 21 is arranged whichacts on a ball or other detent 22 and urges the same partly beyond theouter surface of the extension. The socket is provided with an aperture24 in registration with the aperture 20 in the extension and inregistration with the ball or detent 22 when the socket is in itsoperative position on the extension. When the socket is moved into itsoperative position, the ball is pressed outwardly by the spring to enterpartly into the aperture 24 of the socket, and thus yieldingly retainthe socket on the extension 11 of the tool. Any other means forreleasably holding the socket on the extension of the tool may beprovided.

From the foregoing description, it will be obvious that in the use ofthe magnetic tool described, when the parts thereof are in theiroperative positions as shown in Fig. 1, a workpiece, such as a nut orthe head of a bolt or screw may be positioned in the recess 19 of theend of the socket. The workpiece will then be held in such recess bymeans of the magnet 12. When torque is applied to the shank or stem 10,this torque will be transmitted through the non-circular or drivingportion 17 of the extension to the socket. When end pressure is appliedto the shank, this end pressure will be transmitted by the enlargement14-01? the shank directly to the adjacent end of the socket. By means ofthis construction, the magnet itself is not subjected to any strain ortorque and the relatively thin walled portion of the extension 11surrounding the magnet is also not subjected to torque, and for thatreason, is preferably circular in cross section, so that all of thetorque will be transmitted to the socket by means of the driving portion17 of the extension.

If a socket becomes worn, it can easily be removed from the tool by anendwise pull on the socket which will cause the ball 22 to enter intothe aperture or recess 20 in the extension and thus permit the socketmember to be removed from the tool. The socket member, consequently, mayalso be removed when it is desired to replace the same with anothersocket member having an end aperture or recess 19 of a difierent size orshape to cooperate with workpieces of different sizes or shapes. Sincethe magnet and the extension 11 in which it is housed are subject tovery little wear, it will beobvious that the tool will outlast manysockets.

It is also possible in connection with my improved magnetic tool toprovide a socket which may be reversed end for end. In the constructionshown in Figs. 5 to 7, a socket 27 is provided, the bore of which isofuniform dimension throughout the length of the socket, for example, ofhexagonal form as shown at 28. The socket is provided with a pair ofapertures 29 equally spaced from the opposite ends thereof and either ofthese apertures is adapted to cooperate with a suitable detent membersuch as the ball 22 shown in Figs. 1 to 4 or a plunger 30 as shown inFigs. 5 and 6, which is yieldingly urged outwardly by means of a spring31 located in a hole or recess 32 in the extension 33 of the shank. Whenit is desired to remove the socket from the extension 11 of the tool, itis only necessary to press the plunger 30 inwardly by means of a nail orother device and then pull the socket member endwise from the extension33. The socket member may then be reversed so that the other aperture 29will cooperate with the detent or plunger 30. By means of thisconstruction, the life of the socket may be doubled, since even if theouter end becomes mutilated and damaged by repeated use with the nuts orother workpieces upon which the socket operates, the same may bereversed. When in its reversed position, the relatively short end of thebore which has been damaged by repeated use, is not depended upon totransmit torque, since the portion of the extension 11 of non-circularcross section is considerably longer than the short mutilated endportion of the socket member.

This extension 33 is also of non-magnetic material and may be formedintegral or secured to the shank 10,. and in the particularconstruction, this extension is of noncircular cross section, forexample hexagonal, throughout the length thereof, as clearly shown inFigs. 6 and 7. The sockets used in connection with the constructiondescribed may, of course, be of any good grade of steel, or othermagnetic material, since when a nut or other device is inserted into thecavity in the end of the socket it acts as a keeper to conduct magneticlines of force from the magnet to the socket in case a bar magnet isused. However, with the construction shown in Figs. 1 to 7, the outerend of the magnet may be bifurcated and so magnetized as to form ahorseshoe type of magnet, for holding the nut or other workpiece withinthe end of the socket.

The construction described has the advantages that the magnet is apermanent part of the tool and may be used with a variety of sockets anddriving implements. By securing the magnet in an aperture or recess inthe outer end of the tool, the magnet is protected against damage.

The term non-magnetic is herein used in the practical sense to designatematerials of very low magnetic permeability.

It will be understood that various changes in the details, materials,and arrangements of parts which have been herein described andillustrated in order to explain. the nature of the invention, may bemade by those skilled in the art within the principle and scope of theinvention, as expressed in the appended claims. The constructiondescribed makes it possible to make the socket members of a magneticmaterial, such as a high grade steel, which greatly increases the lifeof the socket members.

I claim as my invention:

1. A magnetic tool including a rotatable solid shank provided with anextension of non-magnetic material having an axially extending aperturein the outer end thereof, a magnet secured in said aperture and beingsubstantially flush with the end thereof, a tubular socket member ofmagnetic material removably secured on said extension means for limitingrearward travel of said socket on said extension, the outer end of saidsocket extending beyond the outer end of said extension to form a recessto receive parts to be rotated by said socket, said parts being held insaid recess by said magnet, a driving connection between said tool andsaid socket, said driving connection being formed by a portion ofnon-circular cross section on said extension, and an interiornoncircular part on said socket formed to cooperate with saidnon-circular portion of said extension, the outer por tion of saidextension being of circular cross section to prevent the transmission oftorque to said socket through References Cited in the file of thispatent UNITED STATES PATENTS 1,887,216 Reynolds Nov. 8, 1932 1,927,844Pfauser Sept. 26, 1933 1,930,238 Helles Oct. 10, 1933 2,260,055 ReardonOct. 21, 1941 2,630,036 Brown Nov. 3, 1953 FOREIGN PATENTS 10,488 GreatBritain Sept. 4, 1885 364,794 France June 9, 1906 340,443 Germany Sept.13, 1921

